JP2007115751A - Substrate heating heater system, vacuum processor, temperature control method, and thin film manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate heating heater system where distribution of heat flux can be controlled in accordance with a state of a device to be installed and a substrate heating condition. <P>SOLUTION: The system is provided with substrate heating heaters 40 comprising a plurality of rod heaters 20, a temperature sensor 3 measuring a temperature of an object 61 to be heated, and a temperature control unit 2 controlling heat generation of the substrate heating heaters 40. The substrate heating heaters 40 are provided with a plurality of heat generation regions. The temperature control unit 2 controls heat flux in a plurality of the heat generation regions so that a measurement temperature becomes a setting temperature based on a plurality of coefficient values, which are previously set in accordance with a plurality of the heat generation regions, the measurement temperatures and the setting temperatures. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a substrate heater system, a vacuum processing apparatus, a temperature control method, and a thin film manufacturing method.

  As a vacuum processing apparatus, a plasma CVD (Chemical Vapor Deposition) apparatus, a sputtering apparatus, and a dry etching apparatus are known. When a substrate is processed in these vacuum processing apparatuses, the substrate is heated by a substrate heater system. This brings the substrate to the desired substrate temperature.

  The uniformity of the in-plane temperature in the substrate installed in the vacuum processing apparatus is important not only for the uniformity of the film quality of the thin film formed on the substrate, but also for the suppression of the warpage of the substrate. In particular, in a large area substrate exceeding 1 m × 1 m, if the in-plane temperature distribution of the substrate exceeds 30 ° C., buckling deformation may occur in the substrate. Here, buckling deformation is a phenomenon in which the thermal deformation of the central part differs from the thermal deformation of the peripheral part due to the temperature difference between the central part and the peripheral part of the substrate, causing a complex deformation that causes the substrate to swell. Say. When buckling deformation occurs, (a) it is necessary to make the temperature distribution in the substrate surface substantially uniform to recover the deformation, and a long waiting time is required until that time. The film quality and film thickness become non-uniform due to temperature distribution and substrate potential state distribution. (C) If the substrate is moved in and out of the film forming chamber without recovering the deformation, the edge of the substrate is not cured in the film forming chamber. It will cause bad effects such as hitting the tool and damaging the substrate. Therefore, as the area of the substrate increases, a technique for suppressing the in-plane temperature distribution of the substrate as much as possible is desired.

  As a related technique, Japanese Patent Application Laid-Open No. 2004-128278 discloses a substrate heating control system and a substrate heating control method. The substrate heating control system includes a heater, a heater cover, a heater temperature measurement unit, a heater cover temperature measurement unit, an input unit, a first PID control unit, a storage unit, a mode switching unit, and a control unit. And a second PID control unit and a thyristor. The heater heats the substrate. The heater cover covers the heater. The heater temperature measuring unit measures and outputs the temperature of the heater. The heater cover temperature measurement unit measures and outputs the temperature of the heater cover. The input unit inputs a set temperature of the heater cover. The first PID control unit receives the temperature setting value of the heater cover and the temperature measurement value of the heater cover, calculates a difference change between the setting value and the measurement value, and performs PI or PID calculation is performed and a first command value is output. The storage unit stores a plurality of preset temperature management modes. The mode switching unit reads the temperature management mode from the storage unit based on the temperature measurement value of the heater cover, and switches the temperature management mode. The control unit performs control in the temperature management mode and outputs a second command value. The second PID control unit receives the temperature measurement value of the heater and the first command value or the second command value, calculates a difference change between the measurement value and the command value, and calculates the difference PI or PID calculation is performed for the change, and the third command value is output. The thyristor performs power control on the heater based on the third command value.

  Japanese Patent Laying-Open No. 2005-142052 discloses a substrate heater. The substrate heater includes a plurality of bar heaters and a plurality of temperature control units connected to each of the plurality of bar heaters. Each of the bar heaters has a plurality of heat generating portions. The plurality of temperature control units respectively control heat fluxes in the plurality of heat generating units. Each of the bar heaters may include a first heat generating portion, a second heat generating portion, and a third heat generating portion as the plurality of heat generating portions. At this time, the second heat generating part is located between the first heat generating part and the third heat generating part.

JP 2004-128278 A JP-A-2005-142052

In order to make the temperature distribution uniform in various apparatus operating conditions on a large-area substrate exceeding 1 m × 1 m, it is generally performed to finely control the temperature of the heat generating portion. However, due to the large heat capacity, the conventional PID control takes time to stabilize, or hunting occurs due to the heat conduction of the adjacent heat generating part, causing problems in application to production equipment. It was.
An object of the present invention is to provide a substrate heater system capable of controlling the distribution of heat flux in accordance with the state of the apparatus in which the substrate is installed and the substrate heating conditions in various apparatus operating conditions, and the use thereof It is to provide a vacuum processing apparatus, a temperature control method, and a thin film manufacturing method.

  Another object of the present invention is to provide a substrate heater system capable of controlling the heat flux so that the substrate temperature distribution is optimized even for a large-area substrate, as well as a vacuum processing apparatus and temperature using the substrate heater system. It is to provide a control method and a thin film manufacturing method.

  Still another object of the present invention is to provide a substrate heater system capable of reaching a desired substrate temperature in a short time while keeping the substrate temperature distribution low even for a large area substrate, and a vacuum processing apparatus using the same And a temperature control method and a thin film manufacturing method.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the best mode for carrying out the invention. These numbers and symbols are added with parentheses to clarify the correspondence between the description of the claims and the best mode for carrying out the invention. However, these numbers and symbols should not be used for interpreting the technical scope of the invention described in the claims.

The substrate heater system of the present invention includes a plurality of heater units (41a to 41e), a temperature sensor (3), and a temperature controller (2). The plurality of heater units (41a to 41e) are arranged in parallel. The temperature sensor (3) measures the temperature of the object (61) heated by the plurality of heater units (41a to 41e). Since the temperature distribution of the substrate (62) is substantially transferred from the temperature distribution of the heater cover (60) on which the substrate (62) is installed, it is important to make the temperature distribution of the heater cover (60) uniform. The temperature sensor (3) is installed at a position where the temperature of the heater cover (60) can be appropriately monitored so as to reach the target set temperature. Usually, since the heat flux is controlled so that the temperature of the heater cover (60) has a substantially uniform temperature distribution, the temperature sensor (3) is installed near the center of the heater cover (60). The temperature controller (2) controls the heat generation of the plurality of heater units (41a to 41e). Each of the plurality of heater units (41a to 41e) includes a plurality of heat generating regions (A1 to A3 / B1 to B3 / C1 to C3 / D1 to D3 / E1 to E3). The temperature control unit (2) includes a plurality of coefficient values (15a) set in advance corresponding to the plurality of heat generation regions (A1 to A3, ..., E1 to E3) of the plurality of heater units (41a to 41e). ), The measured temperature, and the set temperature, so that the measured temperature becomes the set temperature, the plurality of heat generating regions (A1 to A3, ..., E1) of the plurality of heater units (41a to 41e). Each of the heat fluxes in E3) is controlled. By controlling the heat fluxes corresponding to the plurality of heat generating regions (A1 to A3,..., E1 to E3), the temperature distribution of the heater cover (60) becomes substantially uniform.
In the present invention, since coefficient values corresponding to each of the plurality of heat generation regions are set in advance, by using the measured temperature of one temperature sensor (3) and the plurality of coefficient values, the heater cover (60) The heat flux of each of the plurality of heat generation regions suitable for making the temperature distribution substantially uniform can be easily calculated. As a result, the necessary heat flux is provided from the initial stage of the control start in each operating situation, so that the control until reaching the settling temperature is facilitated, and the temperature distribution can be kept small.

  In the substrate heater system, each of the plurality of heater units (41a to 41e) is distributed in a plane and includes a plurality of heat generating portions (26a to 26c). That is, it is possible to use a substrate heater having a structure having a plurality of heat generating portions in a plane facing the heating object (61) of the substrate heater (40). The temperature control unit (2) is configured to generate the plurality of heating units (26a to 26c) of the plurality of heater units (41a to 41e) based on the plurality of coefficient values (15a), the measured temperature, and the set temperature. ) To control the heat flux respectively.

  In the above substrate heater system, each of the plurality of heater units (41a to 41e) includes, for example, at least one rod-shaped heater (20-i to 20-j, i ≦ j). The rod heaters (20-i to 20-j) have a plurality of heat generating portions (26a to 26c). The temperature control unit (2) is configured to generate the plurality of heating units (26a to 26c) of the plurality of heater units (41a to 41e) based on the plurality of coefficient values (15a), the measured temperature, and the set temperature. ) To control the heat flux respectively.

  In the substrate heater system, the temperature controller (2) includes the plurality of heater units (41a to 41e) in addition to the plurality of coefficient values (15a), the measured temperature, and the set temperature. Corresponding to the plurality of operation modes of the vacuum processing apparatus (100) to be performed, the operation mode at the time of control among the plurality of preset heat fluxes set in advance so that the temperature distribution of the heater cover (60) becomes uniform. Based on the corresponding set heat flux, the heat fluxes in the plurality of heat generating regions (A1 to A3,..., E1 to E3) of the plurality of heater units (41a to 41e) are controlled to quickly set temperatures. To change.

  In the substrate heater system, the temperature control unit (2) includes a preceding heat flux setting unit (6), a PID control unit (8), and a ratio setting unit (12). The preceding heat flux setting unit (6) stores the plurality of set heat fluxes and outputs the corresponding set heat flux. The PID control unit (8) performs PI control or PID control based on the measured temperature and the set temperature, and outputs a control heat flux. The ratio setting unit (12) stores a plurality of groups of the plurality of coefficient values set in advance corresponding to a plurality of substrate heating modes, and corresponds to the substrate heating mode at the time of the control among the plurality of groups. Output corresponding group. The temperature control unit (2) is configured to generate the plurality of heat generating regions (A1 to A3,...) Of the plurality of heater units (41a to 41e) based on the corresponding setting heat flux, the control heat flux, and the corresponding group. , E1 to E3) are controlled respectively.

  In the substrate heater system, when the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference (ΔT (c)), the temperature controller (2) is configured to control the corresponding set heat flux and the control. Instead of the heat flux, a preceding heat flux change unit (11) that outputs a preset first heat setting heat flux for startup is further provided. When the difference between the measured temperature and the set temperature is equal to or greater than the first temperature difference (ΔT (c)), it is as follows. That is, the ratio setting unit (12) determines that the start temperature rising mode is one of the plurality of substrate heating modes, and outputs a start corresponding group as the corresponding group corresponding to the start temperature increasing mode. To do. The temperature control unit (2) is configured to generate the plurality of heat generating regions (A1 to A3,...) Of the plurality of heater units (41a to 41e) based on the first setting heat flux for starting and the corresponding group for starting. , E1 to E3) are controlled respectively.

  In the above substrate heater system, when the difference between the measured temperature and the set temperature is greater than or equal to a second temperature difference (ΔT (a)) and less than the first temperature difference (ΔT (c)), it is as follows. . That is, the preceding heat flux changing unit (11) outputs a preset second heat setting heat flux instead of the first heat setting heat flux. The ratio setting unit (12) outputs the activation corresponding group. The temperature control unit (2) is configured to generate the plurality of heating regions (A1 to A3,...) Of the plurality of heater units (41a to 41e) based on the second setting heat flux for starting and the corresponding group for starting. , E1 to E3) are controlled respectively.

  In the above substrate heater system, when the difference between the measured temperature and the set temperature is less than the second temperature difference (ΔT (a)), it is as follows. That is, the preceding heat flux setting unit (6) outputs the corresponding setting heat flux corresponding to the operation mode during control. The PID control unit (8) outputs the control heat flux based on the measured temperature and the set temperature. The ratio setting unit (12) determines that the control automatic mode is one of the plurality of substrate heating modes, and outputs a control automatic correspondence group as a correspondence group corresponding to the control automatic mode. The temperature control unit (2) is configured to generate the plurality of heat generation regions (A1 to A1) of the plurality of heater units (41a to 41e) based on the correspondence setting heat flux, the control heat flux, and the control automatic correspondence group. A3,..., E1 to E3) are controlled respectively.

  The vacuum processing apparatus of the present invention includes a substrate heater system (52), a substrate holder (61), and a discharge electrode (81). The substrate heater system (52) is provided in the film forming chamber (80) and is described in the paragraph above. The substrate holding part (61) is provided in the film forming chamber (80), can hold the substrate (62), is heated by the substrate heater (52), and becomes a ground electrode. The discharge electrode (81) is provided in the film forming chamber (80) and is provided to face the substrate holding part (61).

  The temperature control method of the present invention uses a substrate heater system. Here, the substrate heater system (52) measures the temperatures of the plurality of heater units (41a to 41e) arranged in parallel and the object (60) heated by the plurality of heater units (41a to 41e). And a temperature controller (2) for controlling heat generation of the plurality of heater units (41a to 41e). Each of the plurality of heater units (41a to 41e) includes a plurality of heat generating regions (A1 to A3 / B1 to B3 / C1 to C3 / D1 to D3 / E1 to E3). In the temperature control method, (a) a temperature control unit (2) acquires the measured temperature, and (b) a temperature control unit (2) includes the plurality of heater units (41a to 41e). The measured temperature becomes the set temperature based on a plurality of preset coefficient values (15a) corresponding to the heat generation areas (A1 to A3,..., E1 to E3), the set temperature, and the measured temperature. The heat fluxes in the plurality of heat generating regions (A1 to A3,..., E1 to E3) of the plurality of heater units (41a to 41e) are controlled so that the temperature distribution of the heater cover (60) becomes substantially uniform. Steps.

  In the above temperature control method, here, in the substrate heater system (52), each of the plurality of heater units (41a to 41e) is distributed in a plane, and a plurality of heat generating portions (26a to 26c) are provided. Have. That is, it is possible to use a substrate heater having a structure having a plurality of heat generating portions in a plane facing the heating object (61) of the substrate heater (40). In the step (b), (b1) the temperature controller (2) makes the measured temperature the set temperature based on the plurality of coefficient values (15a), the measured temperature, and the set temperature, and the heater There is provided a step of controlling heat fluxes in the plurality of heat generating portions (26a to 26c) of the plurality of heater units (41a to 41e), respectively, so that the temperature distribution of the cover (60) becomes substantially uniform.

  In the temperature control method described above, the substrate heater system (52) is configured such that each of the plurality of heater units (41a to 41e) includes at least one bar heater (20-i to 20-j, i ≦ j). )including. The rod heaters (20-i to 20-j) have a plurality of heat generating portions (26a to 26c). In the step (b), (b1) the temperature controller (2) makes the measured temperature the set temperature based on the plurality of coefficient values (15a), the measured temperature, and the set temperature, and the heater There is provided a step of controlling heat fluxes in the plurality of heat generating portions (26a to 26c) of the plurality of heater units (41a to 41e), respectively, so that the temperature distribution of the cover (60) becomes substantially uniform.

  In the temperature control method, the step (a) includes: (a1) a temperature control unit (2), a plurality of operation modes of the vacuum processing apparatus (100) in which the plurality of heater units (41a to 41e) are installed; Among these, the step of acquiring the operation mode at the time of control is provided. In the step (b), (b2) the temperature control unit (2) previously corresponds to the plurality of operation modes in addition to the plurality of coefficient values (15a), the measured temperature, and the set temperature. The heater cover (60) temperature is set to be substantially uniform in a desired operation mode, and the plurality of set heat fluxes are set based on the corresponding set heat flux corresponding to the operation mode at the time of control. The heat fluxes in the plurality of heat generating regions (A1 to A3,..., E1 to E3) of the heater units (41a to 41e) are controlled.

  In the temperature control method, the step (a) includes a step (a2) in which the temperature control unit (2) acquires a substrate heating mode at the time of control among a plurality of substrate heating modes. The step (b) includes: (b3) the temperature controller (2) performing PI control or PID control based on the measured temperature and the set temperature to output a control heat flux; and (b4) ) The temperature control unit (2) outputs a corresponding group corresponding to the substrate heating mode at the time of control among the plurality of groups of the plurality of coefficient values set in advance corresponding to the plurality of substrate heating modes. And (b5) the temperature control unit (2) is configured to generate the plurality of heats of the plurality of heater units (41a to 41e) based on the corresponding set heat flux, the control heat flux, and the corresponding group. The heat fluxes in the regions (A1 to A3,..., E1 to E3) are controlled.

  In the above temperature control method, (c) when the difference between the measured temperature and the set temperature is equal to or greater than the first temperature difference (ΔT (c)), the temperature control unit (2) causes the corresponding set heat flux and In place of the control heat flux, the method further includes a step of outputting a preset first heat flux for starting. In the step (b4), (b41) when the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference (ΔT (c)), the temperature control unit (2) performs the plurality of substrate heating modes. And determining a startup temperature increase mode, which is one of the above, and outputting a startup corresponding group as the corresponding group corresponding to the startup temperature increase mode. In the step (b5), (b51) when the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference (ΔT (c)), the temperature control unit (2) sets the first start setting. Based on the heat flux and the corresponding group for activation, the method includes the steps of respectively controlling the heat flux in the plurality of heat generating regions (A1 to A3,..., E1 to E3) of the plurality of heater units (41a to 41e). .

  In the temperature control method, (d) when the difference between the measured temperature and the set temperature is a second temperature difference (ΔT (a)) or more and less than the first temperature difference (ΔT (c)), the temperature control method The unit (2) further includes a step of outputting a preset second startup heat flux instead of the first startup setup heat flux. In the step (b4), (b42) the temperature control is performed when a difference between the measured temperature and the set temperature is a second temperature difference (ΔT (a)) or more and less than the first temperature difference (ΔT (c)). The unit (2) further includes a step of outputting the activation correspondence group. The step (b5) includes the step (b52) when the difference between the measured temperature and the set temperature is equal to or greater than a second temperature difference (ΔT (a)) and less than the first temperature difference (ΔT (c)). The unit (2) is configured to generate the plurality of heat generating regions (A1 to A3,..., E1) of the plurality of heater units (41a to 41e) based on the second setting heat flux for starting and the corresponding group for starting. The method further includes the step of controlling the heat fluxes in E3).

  In the above temperature control method, (e) when the difference between the measured temperature and the set temperature is less than the second temperature difference (ΔT (a)), the temperature control unit (2) enters the operation mode at the time of control. The method further comprises the step of outputting the corresponding setting heat flux. In the step (b3), (b31) when the difference between the measured temperature and the set temperature is less than a second temperature difference (ΔT (a)), the temperature control unit (2) causes the measured temperature and the set temperature to be set. And outputting the control heat flux based on the temperature. In the step (b4), (b43) when the difference between the measured temperature and the set temperature is less than a second temperature difference (ΔT (a)), the temperature control unit (2) causes the plurality of substrate heating modes to be performed. And a step of outputting a control automatic correspondence group as a correspondence group corresponding to the control automatic mode. In the step (b5), (b53) when the difference between the measured temperature and the set temperature is less than a second temperature difference (ΔT (a)), the temperature control unit (2) causes the corresponding set heat flux to Based on the control heat flux and the control automatic correspondence group, the heat fluxes in the plurality of heat generating regions (A1 to A3,..., E1 to E3) of the plurality of heater units (41a to 41e) are respectively controlled. .

  The thin film manufacturing method of the present invention includes (f) a step of holding a substrate (62) in a substrate holding portion (61) as an object to be heated in the film forming chamber (80), and (g) Claim 9 A step of heating the substrate holder (61) and the substrate (62) using the temperature control method according to any one of claims 15 to 15, and (h) grounding in the film forming chamber (80). Plasma of source gas is generated between the substrate holding part (61) as an electrode and the discharge electrode (81) provided so as to face the substrate holding part (61), and the plasma is formed on the substrate (2). Forming a thin film.

  According to the present invention, it is possible to control the distribution of the heat flux according to the state of the apparatus in which the substrate is installed and the substrate heating conditions in various operation states of the apparatus. In addition, the heat flux can be controlled so that the substrate temperature distribution is optimized even for large-area substrates. Furthermore, even for a large-area substrate, a desired substrate temperature can be reached in a short time while keeping the substrate temperature distribution low.

  Embodiments of a substrate heater system, a vacuum processing apparatus, a temperature control method, and a thin film manufacturing method according to the present invention will be described below with reference to the accompanying drawings.

  First, an embodiment of a vacuum processing apparatus using the substrate heater system of the present invention will be described. FIG. 1 is a schematic view showing a configuration of an embodiment of a vacuum processing apparatus using a substrate heater system of the present invention. The vacuum processing apparatus 100 includes a film forming chamber 80, a film forming unit 82, a substrate holding unit 61, and a substrate heater system 52.

The film forming chamber 80 is depressurized by a vacuum pump (not shown), and a source gas (eg, SiH ₄ + H ₂ ) is supplied by a source gas supply device (not shown). The film forming unit 82 is provided in the film forming chamber 80. The film forming chamber 80 includes a discharge electrode (for example, a ladder electrode) 81 connected to a power supply system (not shown).

  The substrate holding part 61 is provided so as to face the discharge electrode 81. The substrate holding unit 61 includes a heater cover 60 and a heat equalizing plate 59. The heater cover 60 is a ground electrode. The heater cover 60 has a mechanism (not shown) that can hold the substrate 62 on the side facing the discharge electrode 81 so as to face the discharge electrode 81. On the other hand, the soaking plate 59 is held on the other side. The substrate 62 and the heater cover 60 are in surface contact. The soaking plate 59 and the heater cover 60 are in surface contact.

  The substrate heater system 52 heats the substrate holder 61, particularly the heater cover 60, so that the temperature distribution is substantially uniform with a desired temperature. A temperature sensor 3, a substrate heater 40, and a temperature control unit 2 are provided. The temperature sensor 3 measures the temperature at an arbitrary point on the heater cover 60. Since it is desirable that the temperature sensor 3 can represent the entire temperature of the heater cover 60, an average value may be adopted by measuring a plurality of points. However, the heat flux is set so that the temperature distribution of the heater cover 60 is substantially uniform. Since it is set, it is usually sufficient to measure the temperature at one point near the center. However, in order to grasp the abnormality of the temperature distribution, monitoring temperature measurement points may be installed and observed as needed. Illustrated in thermocouples. The substrate heater 40 has a heating function. A plurality of bar heaters (heater cartridges) 20 and a plurality of current collecting boxes 32 are provided. The plurality of bar heaters 20 have a heating function. Other than the illustrated form of the rod heater 20, a structure having a plurality of heat generating portions in a plane facing the heating target 61 of the substrate heater 40 can be used. The plurality of current collecting boxes 32 connect the plurality of bar heaters 20 and a power source (not shown). The temperature control unit 2 controls the substrate heater 40. A plurality of heater control units 50 and a control unit 4 are provided. These are exemplified by personal computers and PLCs (Programmable Logic Controllers). The plurality of heater control units 50 controls power supply to the plurality of bar heaters 20. The control unit 4 controls the plurality of heater control units 50 based on the measurement result of the temperature sensor 3. The plurality of heater control units 50 may be outside the film forming chamber 80. The same applies to the control unit 4.

  In the present invention, the substrate 62 is carried into the film forming chamber 80 by a substrate transfer carriage (not shown) and is held by the heater cover 60. The heater cover 60 moves toward the discharge electrode 81 after the substrate transport carriage has left the film forming chamber 80. At the time of substrate processing, the substrate 62 is heated by the substrate heater 40 controlled by the temperature control unit 2 through the soaking plate 59 and the heater cover 60 and maintained at an appropriate temperature.

  Next, an embodiment of the substrate heater system of the present invention will be described. FIG. 2 is a schematic diagram showing the configuration of the embodiment of the substrate heater system of the present invention. In the substrate heater system 52, the temperature sensor 3 measures the temperature of the central portion of the heater cover 60 of the substrate holder 61. The control unit 4 of the temperature control unit 2 controls the plurality of heater control units 50 based on the measurement result of the temperature sensor 3. Each of the plurality of heater control units 50 of the temperature control unit 2 controls the supply of electric power to the corresponding one of the plurality of bar heaters 20 based on the control of the control unit 4 instructing the MV value. Each of the plurality of bar heaters 20 heats the heat equalizing plate 59 and the heater cover 60 by supplying electric power from a corresponding one of the plurality of bar heaters 20. Each of the above controls will be described later.

  FIG. 3 is a schematic diagram showing the configuration of the rod heater in the embodiment of the substrate heater system of the present invention. The rod heater 20 includes an upper heat generating portion 26a, a central heat generating portion 26c, and a lower heat generating portion 26b in this order. These heat generating portions are distributed along the longitudinal direction of the bar heater 20. An upper non-heat generating portion 28a is present at the end of the bar heater 20 on the upper heat generating portion 26a side, and a lower non-heat generating portion 28b is present at the end on the lower heat generating portion 26b side. These non-heat generating parts prevent ground faults and suppress the temperature rise of the current collecting box 32 so that power can be stably supplied to the heat generating parts.

  The outer shell of the rod heater 20 is a tube body 30. The tubular body 30 has a bent portion 31, and is bent at a part of the lower heat generating portion 26b and the lower non-heat generating portion 28b. This is to isolate the lower non-heat generating portion 28b from the substrate holding portion 61 (in the direction of arrow V). One end of the rod heater 20 is connected to the current collection box 32. The current collection box 32 includes a terminal block 33. The terminal block 33 is sealed with an O-ring or the like by using an introduction pipe 34, so that the conductive material passed through the wall surface of the film forming chamber 80, which is a vacuum atmosphere, to the outside in the atmosphere. Line 35 is connected. The conductive wire 35 is connected to the heater control unit 50.

  A plurality of heat generating elements (heat generating elements) whose heat generation density is adjusted by, for example, winding a heat generating element wire in a coil shape are provided inside the tube body 30 so as to correspond to the plurality of heat generating portions. That is, the upper heat generating element 22a is disposed so as to correspond to the upper heat generating portion 26a. A central heating element 22c is disposed so as to correspond to the central heating part 26c. A lower heat generating element 22b is disposed so as to correspond to the lower heat generating portion 26b. The upper heat generating element 22 a is connected in the middle of a conductive wire 24 a having both ends connected to the terminal block 33. The central heat generating element 22 c is connected to the middle of the conductive wire 24 c connected to the terminal block 33 at both ends. The lower heat generating element 22 b is connected in the middle of the conductive wire 24 b connected to the terminal block 33 at both ends. The space inside the tube body 30 may be filled with an insulator made of MgO or the like so that an internal short circuit does not occur in each of the heat generating elements 22a, 22c, 22b and each of the conductive wires 24a, 24c, 24b.

  Electric power is supplied to the conductive lines 24 a, 24 c, and 24 b from the plurality of heater control units 50 through the conductive lines 35. When power is supplied to the conductive wires 24a, 24c, and 24b, the upper heating element 22a, the central heating element 22c, and the lower heating element 22b generate heat. Here, the electric power supplied to the conductive wires 24a, 24c, and 24b is separately controlled by the plurality of temperature control units 50. That is, the heat fluxes in the upper heating element 22a, the central heating element 22c, and the lower heating element 22b are controlled separately. Thereby, it becomes possible to control the distribution of the heat flux of the rod heater 20, particularly the distribution of the heat flux in the longitudinal direction.

  Since the tubular body 30 has the bent portion 31, a part of the lower non-heat generating portion 26 b and a wiring portion such as the current collection box 32 are positioned away from the substrate holding portion 61 (in the direction of arrow V). Thereby, the board | substrate holding | maintenance part 61 can face the part by which heat_generation | fever was controlled without the shield.

  FIG. 4 is a schematic diagram showing the configuration of the substrate heater in the embodiment of the substrate heater system of the present invention. The substrate heater 40 includes a plurality of rod heaters 20. The substrate holding portion 61 that supports the substrate 62 is disposed at a distance so as to face the substrate heater 40. The plurality of rod-shaped heaters 20 are arranged substantially parallel to each other at intervals along the same plane (YZ plane in FIG. 3). The heat generation range 1 (indicated by a one-dot chain line) by the heat generating portion of the substrate heater 40 substantially corresponds to the range of the substrate holding portion 61. With this arrangement, the heat generating part of the substrate heater 40 can be arranged uniformly with respect to the substrate holding part 61. Since the rod-shaped heater 20 and the substrate holding portion 61 are installed at a distance rather than being in close contact with each other, heat is transferred from the rod-shaped heater 20 mainly to the radiant heat transfer to the substrate holding portion 61. The region of the substrate holder 61 corresponding to the pitch between the two is also heated. Further, some temperature distribution is eliminated by heat conduction inside the substrate holding unit 61.

  The pitch (interval) when arranging the plurality of rod heaters 20 is selected so that the temperature distribution in the Y direction of the substrate holder 61 is uniform. For example, the pitch is set to about 2 to 4 times the rod heater diameter. The substrate heater 40 can be considered to have a plurality of heater units in which several bar heaters 20 are grouped. That is, the substrate heater 40 includes a plurality of heater units 41 arranged in parallel in the Y direction. Here, heater units 41a to 41e are provided.

  Since the heat transfer loss amount to the film forming chamber 80 is larger in the vicinity of both ends of the substrate holding portion 61 than in the vicinity of the center, it is necessary to configure the heater units 41a to 41e so that the heat flux can be set larger than that in the vicinity of the center. . That is, it is desirable to change the number of the rod-shaped heaters 20 so that finer heating unit control is possible as the distance from the both ends of the substrate heater 40 becomes closer. For example, the heater unit 41a includes three rod heaters 20-1 to 20-3. The heater unit 41b has six bar heaters 20-4 to 20-9. The heater unit 41c has ten bar heaters 20-10 to 20-19. The heater unit 41d has six bar heaters 20-20 to 20-25. The heater unit 41e has three bar heaters 20-25 to 20-30. One heater unit 41 includes one current collection box 32. A plurality of bar heaters 20 are connected to one current collection box 32.

  The plurality of heater control units 50 provided corresponding to the plurality of bar heaters 20 may be controlled by one heater control unit 50. Alternatively, one heater control unit 50 may control a plurality of bar heaters 20 belonging to the same heater unit 41.

  Using the rod heater 20 or the heater unit 41 is excellent in reducing the weight and cost of the substrate heater 40 because the rod heater 20 does not need to be housed in a box-shaped container. Moreover, the board | substrate heater 40 can be enlarged easily by lengthening the rod-shaped heater 20 to a Z direction, or adding the new rod-shaped heater 20 or the heater unit 41 suitably. That is, even when the substrate 62 becomes large, the substrate heater 40 according to the present invention can be easily applied.

  As described above, each heater unit 41 has three heat generating portions (an upper heat generating portion 26a, a central heat generating portion 26c, and a lower heat generating portion 26b). Accordingly, the heat generation range 1 of the substrate heater 40 has a heat generation area corresponding to (the number of heater units 41) × (the number of heat generating portions). This is shown in FIG. FIG. 5 is a schematic view showing a heat generation region of the substrate heater in the embodiment of the substrate heater system of the present invention. Here, the heat generation range 1 includes heat generation areas A1, A2 and A3, heat generation areas B1, B2 and B3, heat generation areas C1, C2 and C3, heat generation areas D1, D2 and D3, and heat generation areas E1, E2 and E3. . The heat generating areas A1, A2, and A3 correspond to the upper heat generating portion 26a, the central heat generating portion 26c, and the lower heat generating portion 26b in the heater unit 41a, respectively. The heat generating regions B1, B2, and B3 correspond to the upper heat generating portion 26a, the central heat generating portion 26c, and the lower heat generating portion 26b in the heater unit 41b, respectively. The heat generating regions C1, C2, and C3 correspond to the upper heat generating portion 26a, the central heat generating portion 26c, and the lower heat generating portion 26b in the heater unit 41c, respectively. The heat generating regions D1, D2, and D3 correspond to the upper heat generating portion 26a, the central heat generating portion 26c, and the lower heat generating portion 26b in the heater unit 41d, respectively. The heat generating regions E1, E2, and E3 correspond to the upper heat generating portion 26a, the central heat generating portion 26c, and the lower heat generating portion 26b in the heater unit 41e, respectively.

  In the present invention, the temperature distribution of the substrate holding part 61 and the substrate 62 can be further reduced by controlling the temperature for each of the plurality of heat generating regions A1 to A3,. In addition, although the heat_generation | fever range 1 is divided into 15 here, this invention is not limited to this example. For example, when the heat generating range is increased as a result of increasing the heat generating portion by elongating the rod heater 20 in the Z direction or adding the new rod heater 20 and increasing the heater unit 41, the heat generating range 1 is changed. Further, it may be divided into a large number. When the heat generation range 1 becomes small, the heat generation range 1 may be divided into a small number.

  FIG. 6 is a block diagram showing a temperature control unit in the embodiment of the substrate heater system of the present invention. This figure shows the control of the substrate heater unit 41 performed by the control unit 4 and the heater control unit 50 of the temperature control unit 2.

  The control unit 4 includes a preceding heat flux setting unit 6, a calculation unit 7, a PID control unit 8, a calculation unit 9, a mode switching unit 10, a preceding heat flux change unit 11, a ratio setting unit 12, a limiter 13, and an MV value conversion unit. 14.

  The preceding heat flux setting unit 6 stores a plurality of preceding heat fluxes Qs corresponding to the plurality of operation modes of the vacuum processing apparatus 100. Then, based on the operation mode command from the mode switching unit 10, the preceding heat flux Qs corresponding to the operation mode command is output to the calculation unit 9.

  Here, the operation mode includes, for example, a production mode in which the substrate 62 is heated through the heater cover 60 during film formation, a standby mode in which the substrate 62 is heated through the heater cover 60 before film formation, and a heater cover. This is a baking mode in which the heater cover 60 is heated before the substrate 60 holds the substrate 62. The preceding heat flux Qs is one of the heat flux command values generated by the substrate heater 40, and a predetermined value (a constant value) is set in advance for each operation mode. This is provided separately from the control heat flux ΔQ (variation based on the measurement result of the temperature sensor 3, which will be described later) calculated by the PID control. In the present invention, by controlling the substrate heater 40 using the preceding heat flux Qs as a base, the heater cover 60 can be quickly reached the set temperature, and the control heat flux ΔQ can be corrected and controlled gently. Thus, occurrence of hunting can also be prevented.

  Based on the set temperature T (HC) set of the heater cover 60 and the temperature T (HC) pv of the heater cover 60 output from the temperature sensor 3, the calculation unit 7 calculates the temperature difference ΔT (HC) that is the difference between the two. = T (HC) set−T (HC) pv is calculated and output to the PID control unit 8 and the mode switching unit 10.

  The PID control unit 8 executes at least one control (eg, PI control) of proportional control, integral control, and differential control based on ΔT (HC), and commands the heat flux generated by the substrate heater 40. A control heat flux ΔQ, which is one of the values, is calculated and output to the calculation unit 9.

  Based on the preceding heat flux Qs output from the preceding heat flux setting unit 6 and the control heat flux ΔQ output from the PID control unit 8, the calculation unit 9 calculates the heat flux Q0 = Qs + ΔQ which is the sum of the two. And output to the preceding heat flux changing unit 11.

  There are a plurality of substrate heating modes for heating the substrate heater 40. The substrate heating mode is, for example, a startup temperature raising mode for rapidly raising the temperature of the substrate holding unit 61 having a predetermined temperature or lower, and a control automatic mode for performing PID control using the preceding heat flux. The preceding heat flux change unit 11 stores a startup temperature increase heat flux Q1 (Q1 (t), Q1L) corresponding to the startup temperature increase mode. Then, based on the substrate heating mode command from the mode switching unit 10, among the heat flux Q0 and the startup temperature rising heat flux Q1 (t), Q1L supplied from the calculation unit 9, it corresponds to the substrate heating mode command. Is output to the ratio setting unit 12 as the heat flux Q. The heat flux Q output here indicates the heat flux of the substrate heater 40 with respect to the heat generation area where the temperature sensor 3 measures the temperature.

  The ratio setting unit 12 stores a plurality of coefficient value tables 15 corresponding to a plurality of substrate heating modes. FIG. 7 is a diagram illustrating an example of a plurality of coefficient value tables. FIG. 7A shows a coefficient value table 15a corresponding to the control automatic mode. FIG. 7B is a coefficient value table 15b corresponding to the startup temperature raising mode. Each coefficient value in each coefficient value table 15 corresponds to each heat generation area (A1,..., E3) of the heat generation range 1. For example, referring to FIG. 7A, the coefficient value C (A1) of the heat generation area A1 is 2.7. Similarly, C (A2) = 1.8, C (A3) = 3.5, C (B1) = 1.5, C (B2) = 1.0, C (B3) = 2.0, C (C1) = 1.5, C (C2) = 1.0, C (C3) = 2.0, C (D1) = 1.5, C (D2) = 1.0, C (D3) = 2 0.0, C (E1) = 2.7, C (E2) = 1.8, C (E3) = 3.5. The same applies to FIG. 7B.

The ratio setting unit 12 selects a coefficient value table 15 corresponding to the substrate heating mode command from a plurality of coefficient value tables 15 based on the substrate heating mode command from the mode switching unit 10. Then, the heat flux Q output from the preceding heat flux change unit 11 and the selected coefficient value table 15 are multiplied to calculate the heat flux Qr of each heat generation region and output to the limiter 13. When the heat generation range 1 has 15 heat generation regions, it has 15 heat fluxes Qr. FIG. 8 is a diagram illustrating an example of the heat flux Qr in each heat generating region. FIG. 8A shows the heat flux Qr of each heat generation region corresponding to the control automatic mode. The case of heat flux Q = 0.3 (W / cm ² ) is shown. FIG. 8B shows the heat flux Qr of each heat generation region corresponding to the startup temperature raising mode. The case of heat flux Q = 0.5 (W / cm ² ) is shown. For example, referring to FIG. 8A, the heat flux Qr (A1) = 0.81 (W / cm ² : hereinafter omitted) of the heat generation region A1. Similarly, Qr (A2) = 0.54, Qr (A3) = 1.05, Qr (B1) = 0.45, Qr (B2) = 0.3, Qr (B3) = 0.6, Qr (C1) = 0.45, Qr (C2) = 0.3, Qr (C3) = 0.6, Qr (D1) = 0.45, Qr (D2) = 0.3, Qr (D3) = 0 .6, Qr (E1) = 0.81, Qr (E2) = 0.54, Qr (E3) = 1.05. For example, when the heat flux Qr (A1) = 0.81 in the heat generation area A1, the upper heat generating portion 26a in each of the plurality of bar heaters 20 belonging to the heater unit 41a has a heat flux Qr (A1) = 0.81 (W / Cm ² ). The same applies to FIG.

  The mode switching unit 10 is connected to the preceding heat flux setting unit 6 based on a signal from a host control device (eg, a control unit of the vacuum processing apparatus 100, not shown), a temperature difference ΔT (HC) or an operator input. The operation mode command is output to the preceding heat flux changing unit 11 and the ratio setting unit 12, respectively.

  The limiter 13 sets an upper limit so that the heat flux Qr becomes a heat flux that exceeds the capacity of each rod heater 20 and does not cause equipment damage due to abnormal heat generation. The heat flux Qr of each heat generation region from the ratio setting unit 12 is output to the MV value conversion unit 14 while limiting the upper limit. If the capacity of the bar heater 20 is sufficiently high, it may be omitted.

  The MV value conversion unit 14 converts the heat flux Qr (A1),..., Qr (E3) of each heat generation region into the MV value (A1),..., MV value (E3) of each heat generation region. Then, the MV value (A1),..., MV value (E3) of each heat generation region is output to the corresponding heater control unit 50. For example, heat fluxes Qr (A1), Qr (A2) = 0.54, and Qr (A3) = 1.05 are converted into MV value (A1), MV value (A2), and MV value (A3). To do. Then, the MV value (A1), the MV value (A2), and the MV value (A3) are output to at least one heater control unit 50 that controls the plurality of bar heaters 20 belonging to the heater unit 41a.

The heater control unit 50 includes a current value conversion unit 15 and a power controller 16.
The current value conversion unit 15 converts the MV value supplied from the MV value conversion unit 14 into a current value I in the rod heater 20 and outputs the current value I to the power controller 16. For example, in at least one heater control unit 50 that controls the plurality of bar heaters 20 belonging to the heater unit 41a, the current value conversion unit 15 includes the MV value (A1) and the MV value (A2) supplied from the MV value conversion unit 14. ) And MV value (A3) are converted into current values I (A1), I (A2), and I (A3) in the rod heater 20 and output to the power controller 16.

  Based on the current value I supplied from the current value converter 15, the power controller 16 causes a current having a magnitude of the current value I to flow through the rod heater 20. For example, in at least one heater control unit 50 that controls the plurality of bar heaters 20 belonging to the heater unit 41a, the power controller 16 uses the current value I (A1) and the current value I (A2) supplied from the current value conversion unit 15. ), The current having the magnitude of the current value I (A1) of the rod heater 20 is based on the current value I (A3), and the current having the magnitude of the current value I (A2) is middle-heated. The current having the magnitude of the current value I (A3) is supplied to the part 26c through the lower heating part 26b.

  The heat equalizing plate 59 and the heater cover 60 are heated by the heat generated by the rod-shaped heater 20 to raise the temperature. Accordingly, if the substrate 62 is held on the heater cover 60, the temperature of the substrate 62 is increased. The temperature of the heater cover 60 is measured by the temperature sensor 3 and fed back to the control unit 4.

  Hereinafter, an embodiment of a temperature control method using the substrate heater system of the present invention will be described. FIG. 9 is a flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention.

(1) Step S01
The calculation unit 7 calculates a temperature difference ΔT (HC) that is a difference between the set temperature T (HC) set of the heater cover 60 and the temperature T (HC) pv of the heater cover 60 from the temperature sensor 3 to switch the mode. Output to the unit 10 and the PID control unit 8.
The mode switching unit 10 determines whether ΔT (HC) ≧ 0. When ΔT (HC) <0 (No), the mode switching unit 10 determines that the control automatic mode is selected, and proceeds to step S04. If ΔT (HC) ≧ 0 (Yes), the process proceeds to step S02.
(2) Step S02
The mode switching unit 10 stores a temperature difference ΔT (a) that is a preset reference. Then, it is determined whether or not ΔT (HC) ≦ ΔT (a). When ΔT (HC)> ΔT (a) (No), the mode switching unit 10 determines the startup temperature raising mode, and proceeds to step S03. If ΔT (HC) ≦ ΔT (a) (Yes), the process proceeds to step S04.
(3) Step S03
The temperature of the substrate heater 40 is controlled in the startup temperature raising mode.
(4) Step S04
The temperature of the substrate heater 40 is controlled in the control automatic mode.

  As described above, the temperature of the substrate heater 40 can be controlled to bring the heater cover 60 to a desired temperature.

  In the present invention, the temperature control substrate heating mode is applied when the temperature difference between the set temperature and the measured temperature is large, and when the temperature difference between the set temperature and the measured temperature is small. It is divided into modes. Therefore, by properly using the substrate heating mode according to the situation, it is possible to quickly raise the temperature to the set temperature while suppressing the temperature distribution to be small.

  Next, a control automatic program in the embodiment of the temperature control method using the substrate heater system of the present invention will be described. FIG. 12 is a flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention. Here, temperature control of the substrate heater 40 in the control automatic mode of S04 is shown.

  First, the mode switching unit 10 outputs an operation mode command to the preceding heat flux setting unit 6 based on a signal from the host controller. Based on the operation mode command, the preceding heat flux setting unit 6 outputs the preceding heat flux Qs corresponding to the operation mode command to the calculation unit 9 (S11). On the other hand, the PID control unit 8 performs PID control based on the temperature difference ΔT (HC), calculates the control heat flux ΔQ, and outputs it to the calculation unit 9 (S12). The calculation unit 9 calculates the heat flux Q0 = Qs + ΔQ based on the preceding heat flux Qs and the control heat flux ΔQ, and outputs it to the preceding heat flux changing unit 11 (S13).

  The mode switching unit 10 determines that the mode switching unit 10 is in the control automatic mode, and outputs a substrate heating mode command indicating the control automatic mode to the preceding heat flux changing unit 11. Based on the substrate heating mode command, the preceding heat flux changing unit 11 selects the heat flux Q0 corresponding to the substrate heating mode command from the heat flux Q0 and the startup temperature rising heat flux Q1 supplied from the calculation unit 9. The heat flux Q is output (S14).

  The mode switching unit 10 also outputs a substrate heating mode command indicating the control automatic mode to the ratio setting unit 12. The ratio setting unit 12 selects the coefficient value table 15a (FIG. 7A) corresponding to the substrate heating mode command from the plurality of coefficient value tables 15 based on the substrate heating mode command. Then, the heat flux Q and the coefficient value table 15a are multiplied to calculate the heat flux Qr (FIG. 8A) of each heat generation region. And it outputs to the limiter 13 (S15).

  The limiter 13 limits the upper limit to the upper limit allowable value when the heat flux Qr (FIG. 8A) becomes higher than the capacity of each rod heater 20, and outputs the limit to the MV value conversion unit 14. (S16). The MV value conversion unit 14 converts the heat flux Qr (A1),..., Qr (E3) of each heat generation region into the MV value (A1),..., MV value (E3) of each heat generation region. Then, the MV value (A1),..., MV value (E3) of each heat generation region is output to the corresponding heater control unit 50 (S17).

  The current value conversion unit 15 converts the MV value supplied from the MV value conversion unit 14 into a current value I in the rod heater 20 and outputs the current value I to the power controller 16 (S18). Based on the current value I supplied from the current value conversion unit 15, the power controller 16 causes a current having the magnitude of the current value I to flow through the rod heater 20 (S19).

  By the temperature control of the substrate heater 40 as described above, the heater cover 60 is controlled to a desired temperature.

  In the present invention, in the control automatic mode, the preceding heat flux set in advance according to the operation mode is used as the base of the heat flux, and the remaining small fluctuation portion is PID-controlled. That is, heating is performed with a small temperature distribution using only the preceding heat flux, and the remaining fine control is performed by the PID control, so that the heater cover 60 can quickly reach a desired temperature even in a device having a large heat capacity. At the same time, it is possible to perform highly accurate and stable control in which hunting is prevented, and the temperature distribution can be kept extremely small.

  Further, in the present invention, control is performed to determine the heat flux in the plurality of heat generation regions of the heater cover 60 based on the temperature of any one heat generation region (for example, the central heat generation region) of the heater cover 60. . This has the following differences compared to the case where each of the plurality of heat generating regions independently measures the temperature and independently controls the heat flux. That is, each heat generating area transfers heat between the surrounding heat generating areas. In the film forming process of the substrate, the heat transfer state changes due to the pressure atmosphere in the film forming chamber 80, or the substrate 62 is carried in and out. There are changes in the amount of heat transfer with the heater cover 60 and changes in the amount of heat input from the plasma during the film forming process. Since the amount of heat from the surrounding heat generation area that is independently controlled changes from time to time as a disturbance, the control of the heat generation area becomes very complicated. For this reason, an increase in calculation time and an increase in the burden on the control device occur, and it takes time to stabilize due to the large constant of the heat capacity of each heating target area of the heater cover 60. It becomes difficult to heat uniformly. As a result, it becomes difficult to obtain a sufficiently uniform temperature distribution. In the present invention, for each of the plurality of heat generation regions, an appropriate heat flux ratio in various operating conditions is experimentally grasped in advance and stored as a coefficient value table. Thereby, by determining the heat flux of one of the plurality of heat generation regions, the heat flux of the other heat generation regions can be appropriately determined. As a result, even in the heating control of a device having a large heat capacity, it is possible to heat the heater cover 60 quickly and substantially uniformly without increasing the calculation time and increasing the burden on the control device.

  In the present invention, even when the substrate heater 40 is changed by changing the size of the substrate 62, appropriate control can be similarly performed by changing the coefficient value table.

  FIG. 13 is another flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention. Here, temperature control of the substrate heater 40 in the startup temperature raising mode 1 is shown.

  First, the mode switching unit 10 outputs an operation mode command to the preceding heat flux setting unit 6 based on a signal from the host controller. Based on the operation mode command, the preceding heat flux setting unit 6 outputs the preceding heat flux Qs corresponding to the operation mode command to the calculation unit 9. On the other hand, the PID control unit 8 executes PID control based on the temperature difference ΔT (HC), calculates the control heat flux ΔQ, and outputs the control heat flux ΔQ to the calculation unit 9. The calculation unit 9 calculates the heat flux Q0 = Qs + ΔQ based on the preceding heat flux Qs and the control heat flux ΔQ, and outputs it to the preceding heat flux change unit 11. In the startup temperature raising mode 1, these may be skipped.

  The mode switching unit 10 determines that the startup temperature raising mode 1 is in effect. The mode switching unit 10 determines whether or not ΔT (HC)> ΔT (c) (S21). If ΔT (HC)> ΔT (c) (Yes), the measurement temperature is too low, and the process proceeds to step S22. When ΔT (HC) ≦ ΔT (c) (No), since the measured temperature is not too low, the process proceeds to step S25. Here, ΔT (c) is a preset temperature difference and is stored in the mode switching unit 10.

  When ΔT (HC)> ΔT (c) (Yes), the mode switching unit 10 sends a substrate heating mode command indicating the startup temperature raising mode (ΔT (HC)> ΔT (c)) to the preceding heat flux changing unit 11. Output. Based on the substrate heating mode command, the preceding heat flux changing unit 11 corresponds to the substrate heating mode command among the heat flux Q0 and the startup temperature rising heat flux Q1 (t), Q1L supplied from the calculation unit 9. The starting temperature rising heat flux Q1 (t) is output as the heat flux Q (S22). Here, Q1 (t) is calculated by increasing ΔT (HC) ≦ ΔT after increasing the heat flux to 100% with a predetermined temperature gradient so that a large load is not suddenly generated in the substrate heater 40, the controller 50, and the like. It is a function of heat flux that keeps the heat flux at 100% until (c).

  Subsequently, substrate heater current control is performed (S23). This is the same as S15 to S19 except that the control automatic mode is changed to the startup temperature raising mode. That is, first, the mode switching unit 10 also outputs a substrate heating mode command indicating the startup temperature raising mode to the ratio setting unit 12. Based on the substrate heating mode command, the ratio setting unit 12 selects the coefficient value table 15b (FIG. 7B) corresponding to the substrate heating mode command from the plurality of coefficient value tables 15. Then, the heat flux Q and the coefficient value table 15b are multiplied to calculate the heat flux Qr (FIG. 8B) of each heat generation region. And it outputs to the limiter 13. The limiter 13 limits the upper limit to the upper limit allowable value when the heat flux Qr (FIG. 8 (b)) exceeds the capacity of each bar heater 20, and outputs it to the MV value conversion unit 14. To do. The MV value conversion unit 14 converts the heat flux Qr (A1),..., Qr (E3) of each heat generation region into the MV value (A1),..., MV value (E3) of each heat generation region. Then, the MV value (A1),..., MV value (E3) of each heat generation region is output to the corresponding heater control unit 50. The current value conversion unit 15 converts the MV value supplied from the MV value conversion unit 14 into a current value I in the rod heater 20 and outputs the current value I to the power controller 16. Based on the current value I supplied from the current value converter 15, the power controller 16 causes a current having a magnitude of the current value I to flow through the rod heater 20. In this way, the substrate heater 40 is controlled, and the heater cover 60 is heated.

  The calculation unit 7 calculates the temperature difference ΔT (HC) and outputs it to the mode switching unit 10 and the PID control unit 8. The mode switching unit 10 determines whether or not ΔT (HC) ≦ ΔT (c) (S24). If ΔT (HC)> ΔT (c) (No), the process returns to step S23 because heating is insufficient. When ΔT (HC) ≦ ΔT (c) (Yes), it is determined that the predetermined heating is completed, and the process proceeds to step S25.

The operations of the preceding heat flux setting unit 6, the PID control unit 8, and the calculation unit 9 are omitted. You may skip it.
In the case of ΔT (HC) ≦ ΔT (c), the mode switching unit 10 outputs a substrate heating mode command indicating the startup temperature raising mode (ΔT (HC) ≦ ΔT (c)) to the preceding heat flux changing unit 11. Based on the substrate heating mode command, the preceding heat flux changing unit 11 corresponds to the substrate heating mode command among the heat flux Q0 and the startup temperature rising heat flux Q1 (t), Q1L supplied from the calculation unit 9. The starting temperature raising heat flux Q1L is output as the heat flux Q (S25). Here, Q1L is the maximum heat flux in a range in which the actual heater cover temperature value: T (HC) is less likely to overshoot the heater cover temperature set value: ΔT (HC) set.

  Subsequently, the same substrate heater current control as in S23 is performed (S26). However, the heat flux Q is Q1L. Details are omitted.

  The calculation unit 7 calculates the temperature difference ΔT (HC) and outputs it to the mode switching unit 10 and the PID control unit 8. The mode switching unit 10 determines whether or not ΔT (HC) ≦ ΔT (a) (S27). If ΔT (HC)> ΔT (a) (No), the process returns to step S26 because heating is insufficient. When ΔT (HC) ≦ ΔT (a) (Yes), it is determined that the predetermined heating is finished, and the startup temperature raising mode is finished.

  By the temperature control of the substrate heater 40 as described above, it is possible to quickly reach the temperature range that can be controlled in the control automatic mode. Further, at this time, the heat fluxes Qr (A1),..., Qr (E3) of each heat generating region are values obtained experimentally in advance so as to reduce the temperature distribution of the heater cover 60. The temperature distribution of 60 is substantially uniform, and a good one can be obtained.

  In the present invention, in order to shorten the start-up time of a device having a large heat capacity such as the heater cover 60 for the large area substrate 62 (to make the measurement temperature reach the set temperature in a short time), PID control is not initially performed. , Using a preset prior heat flux. The preceding heat flux is set so that the temperature distribution of the heater cover 60 can be reached in a shortest time up to a predetermined temperature while maintaining a substantially uniform temperature distribution. Therefore, the time taken to reach the set temperature as a whole can be greatly reduced.

  In the present invention, even near the set temperature, a predetermined temperature close to the set temperature can be reached in the shortest time, and in order to prevent overshoot, ΔT (a) ≦ ΔT (HC) ≦ ΔT (c) In this period, the preceding heat flux for starting temperature rise: Q1L is set to an appropriate value. Therefore, the time required to reach the set temperature as a whole can be further shortened by using the preceding heat flux of Q1L for starting and raising the temperature.

  FIG. 10 is a graph showing an example of temporal changes in heat flux and heater cover temperature in the embodiment of the temperature control method using the substrate heater system of the present invention. The left vertical axis is the value of the heat flux Q output from the preceding heat flux changing unit 11. The right vertical axis represents the heater cover temperature T (HC) pv. Curve R1 is the heater cover temperature T (HC) pv, and curve R2 is the heat flux Q. In the figure, Z1 is the period of the startup temperature increase mode, Z2 is the period of the startup temperature increase mode (ΔT (HC)> ΔT (c)), and Z3 is the start temperature increase mode (ΔT (HC) ≦ ΔT ( c)). Z4 is the period of the control automatic mode.

(1) Time t0
Referring also to FIG. 9, the result of S01 is Yes and the result of S02 is No, so the substrate heating mode is the startup temperature increase mode of S03. Referring also to FIG. 13, since the temperature of the heater cover 60 at t0 is room temperature (RT), the result of S21 is Yes, and the startup temperature raising heat flux Q1 (t) is selected as the heat flux Q in S22. .
(2) Time t0 to t2
The substrate heater current control in S23 is executed. As shown by the heat flux Q1 (t) in the curve R2, after increasing the heat flux to 100% at a predetermined temperature gradient, until ΔT (HC) ≦ ΔT (c) (t1 to t2) Keep the heat flow rate at 100%. At this time, the temperature of the heater cover 60 gradually increases.
(3) Time t2
ΔT (HC) ≦ ΔT (c) is reached. That is, since the result of S24 is Yes, the startup temperature rising heat flux Q1L is selected as the heat flux Q in S25.
(4) Time t2 to t3
The substrate heater current control in S26 is executed. As shown by the curve R2, the heat flux is a constant value of Q1L. At this time, the temperature of the heater cover 60 gradually increases further.
(5) Time t3
ΔT (HC) ≦ ΔT (a) is reached. That is, since the result of S27 is Yes, the startup temperature raising mode is terminated assuming that the predetermined heating is completed. Thereafter, the control automatic mode of S04 is started.
(6) After Time t3 Referring also to FIG. 12, the temperature of the substrate heater 40 is controlled by gently correcting and controlling the control heat flux ΔQ in the control automatic mode of S11 to S19. The fact that the heat flux curve R2 has a wave-like shape indicates a situation in which gradual control is performed with respect to repeated substrate loading, film forming processing, and substrate unloading by continuous production processing.

  By using such a temperature control method, in the startup temperature raising mode, the time required for the startup temperature raising can be shortened to 2/3 or less. In addition, the in-plane temperature distribution could be within ± 10 ° C. Similarly, in the control automatic mode, the in-plane temperature distribution can be within ± 10 ° C.

  FIG. 11 is a graph showing an example of temporal changes in heat flux and heater cover temperature in the embodiment of the temperature control method using the substrate heater system of the present invention. The left vertical axis is the value of the heat flux Q output from the preceding heat flux changing unit 11. The right vertical axis represents the heater cover temperature T (HC) pv. Curve R1 is the heater cover temperature T (HC) pv, and curve R2 is the heat flux Q. In the figure, Z4 and Z6 are periods of the control automatic mode. Z5 is the period of the startup temperature raising mode.

(1) Time t4 to t5
Referring also to FIG. 12, since the result of S01 is No or the results of S1 to S2 are Yes, the substrate heating mode is the control automatic mode of S04. That is, the temperature control of the substrate heater 40 is performed in the control automatic mode of S11 to S19. The fact that the heat flux curve R2 has a wave-like shape indicates a situation in which gradual control is performed with respect to repeated substrate loading, film forming processing, and substrate unloading by continuous production processing.
(2) Time t5 to t6
The power source of the substrate heater 40 is temporarily turned off. The heat flux Q becomes 0, and the heater cover temperature T (HC) pv decreases. Such a state occurs due to a self-cleaning performed during the continuous production process of film formation or a trouble stop of the apparatus due to some abnormality.
(3) Time t6
The power source of the substrate heater 40 is turned on. Referring also to FIG. 9, the result of S01 is Yes and the result of S02 is No, so the substrate heating mode is the startup temperature increase mode of S03. Referring also to FIG. 13, since the temperature of the heater cover 60 at t6 is ΔT (HC)> ΔT (b), the result of S21 is Yes, and the startup temperature rising heat flux Q1 (t) is the heat flux at S22. Selected as Q.
(4) Time t6 to t7
The substrate heater current control in S23 is executed. As indicated by the heat flux Q1 (t) in the curve R2, the heat flux is increased to 100% at a predetermined temperature gradient until ΔT (HC) ≦ ΔT (c). Keep it. At this time, the temperature of the heater cover 60 gradually increases.
(5) Time t7
ΔT (HC) ≦ ΔT (c) is reached. That is, since the result of S24 is Yes, the startup temperature rising heat flux Q1L is selected as the heat flux Q in S25.
(6) Time t7 to t8
The substrate heater current control in S26 is executed. As shown by the curve R2, the heat flux is a constant value of Q1L. At this time, the temperature of the heater cover 60 gradually increases further.
(7) Time t8
ΔT (HC) ≦ ΔT (a) is reached. That is, since the result of S27 is Yes, the startup temperature raising mode is terminated assuming that the predetermined heating is completed. Thereafter, the control automatic mode of S04 is started.
(8) After time t8 Referring also to FIG. 12, the temperature of the substrate heater 40 is controlled in the automatic control mode of S11 to S19.

  In the case of the control in FIG. 11, the determination of “ΔT (HC)> ΔT (c)” in S21 in FIG. 13 is also made as “ΔT (HC)> ΔT (b) (> ΔT (c))”. good. Alternatively, ΔT (b) = ΔT (c) may be simply used.

  By using such a temperature control method, the temperature of the heater cover 60 can be made substantially uniform by using the startup temperature raising mode even when the power supply of the substrate heater is turned off once and the heater cover temperature is greatly reduced. The time to return to the set temperature while maintaining the temperature can be greatly shortened. In addition, also in this case, the in-plane temperature distribution of the substrate could be within ± 10 ° C.

  In the present invention, hunting that occurs when PID control is performed on each of the plurality of heat generating portions by giving a predetermined heat flux to the plurality of heat generating portions that have been pre-verified in various operating states. Prolonged temperature stabilization can be greatly suppressed, and a rapid and uniform temperature distribution can be obtained.

FIG. 1 is a schematic view showing a configuration of an embodiment of a vacuum processing apparatus using a substrate heater system of the present invention. FIG. 2 is a schematic diagram showing the configuration of the embodiment of the substrate heater system of the present invention. FIG. 3 is a schematic diagram showing the configuration of the rod heater in the embodiment of the substrate heater system of the present invention. FIG. 4 is a schematic diagram showing the configuration of the substrate heater in the embodiment of the substrate heater system of the present invention. FIG. 5 is a schematic view showing a heat generation region of the substrate heater in the embodiment of the substrate heater system of the present invention. FIG. 6 is a block diagram showing a temperature control unit in the embodiment of the substrate heater system of the present invention. FIG. 7 is a diagram illustrating an example of a plurality of coefficient value tables. FIG. 8 is a diagram illustrating an example of the heat flux Qr in each heat generating region. FIG. 9 is a flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention. FIG. 10 is a graph showing an example of temporal changes in heat flux and heater cover temperature in the embodiment of the temperature control method using the substrate heater system of the present invention. FIG. 11 is a graph showing an example of temporal changes in heat flux and heater cover temperature in the embodiment of the temperature control method using the substrate heater system of the present invention. FIG. 12 is a flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention. FIG. 13 is another flowchart showing an embodiment of a temperature control method using the substrate heater system of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat generation range 2 Temperature control part 3 Temperature sensor 4 Control part 6 Advancing heat flux setting part 7 Arithmetic part 8 PID control part 9 Arithmetic part 10 Mode switching part 11 Advancing heat flux change part 12 Ratio setting part 13 Limiter 14 MV value conversion part 20, 20-1, ..., 20-30 Bar heater (heater cartridge)
22 heating element 22a upper heating element 22b lower heating element 22c central heating element 24, 24a, 24c, 24b conductive wire 26 heating part 26a upper heating part 26c central heating part 26b lower heating part 28 non-heating part 28a upper non-heating part 28b lower part Non-heating part 30 Tubing body 31 Bending part 32 Current collecting box 33 Terminal block 34 Introduction pipe 35 Conductive wire 40 Substrate heater 41, 41a, 41b, 41c, 41d, 41e Heater unit 50 Heater control unit 52 Substrate heater system 59 Heat plate 60 Heater cover 61 Substrate holder 62 Substrate 80 Film forming chamber 81 Discharge electrode (ladder electrode)
100 Vacuum processing equipment

Claims (18)

A plurality of heater units arranged in parallel;
A temperature sensor for measuring the temperature of an object heated by the plurality of heater units;
A temperature control unit that controls heat generation of the plurality of heater units,
Each of the plurality of heater units includes a plurality of heat generation regions,
The temperature control unit is configured such that the measured temperature becomes the set temperature based on a plurality of coefficient values set in advance corresponding to the plurality of heat generation regions of the plurality of heater units, the measured temperature, and the set temperature. As described above, the substrate heater system that controls heat fluxes in the plurality of heat generation regions of the plurality of heater units, respectively. In the substrate heater system according to claim 1,
Each of the plurality of heater units is distributed in a plane and has a plurality of heat generating portions,
The temperature control unit controls a heat flux in each of the plurality of heat generating units of the plurality of heater units based on the plurality of coefficient values, the measured temperature, and the set temperature, respectively. In the substrate heater system according to claim 1,
Each of the plurality of heater units includes at least one bar heater,
The bar heater has a plurality of heat generating parts,
The temperature control unit controls a heat flux in each of the plurality of heat generating units of the plurality of heater units based on the plurality of coefficient values, the measured temperature, and the set temperature, respectively. In the substrate heater system according to any one of claims 1 to 3,
The temperature control unit includes a plurality of preset values corresponding to a plurality of operation modes of a vacuum processing apparatus in which the plurality of heater units are installed in addition to the plurality of coefficient values, the measured temperature, and the set temperature. A substrate heater system that controls heat fluxes in the plurality of heat generation regions of the plurality of heater units based on a corresponding set heat flux corresponding to an operation mode at the time of control among the set heat fluxes. In the substrate heater system according to claim 4,
The temperature controller is
A preceding heat flux setting unit that stores the plurality of set heat fluxes and outputs the corresponding set heat flux;
Based on the measured temperature and the set temperature, a PID control unit that performs PI control or PID control and outputs a control heat flux;
A ratio setting for storing a plurality of groups of the plurality of coefficient values set in advance corresponding to a plurality of substrate heating modes and outputting a corresponding group corresponding to the substrate heating mode at the time of control among the plurality of groups The department and
The temperature control unit controls a heat flux in each of the plurality of heat generation regions of the plurality of heater units based on the corresponding setting heat flux, the control heat flux, and the corresponding group, respectively. In the substrate heater system according to claim 5,
When the difference between the measured temperature and the set temperature is equal to or greater than the first temperature difference, the temperature control unit replaces the corresponding set heat flux and the control heat flux with a preset first start set heat flux. Is further provided with a preceding heat flux changing unit that outputs
When the difference between the measured temperature and the set temperature is not less than the first temperature difference,
The ratio setting unit determines a startup temperature increase mode that is one of the plurality of substrate heating modes, and outputs a start corresponding group as the corresponding group corresponding to the start temperature increase mode,
The temperature control unit controls a heat flux in each of the plurality of heat generation regions of the plurality of heater units based on the first setting heat flux for activation and the corresponding group for activation, respectively. In the substrate heater system according to claim 6,
When the difference between the measured temperature and the set temperature is a second temperature difference or more and less than the first temperature difference,
The preceding heat flux changing unit outputs a preset second startup heat flux instead of the first startup setup heat flux,
The ratio setting unit outputs the activation correspondence group,
The temperature control unit controls a heat flux in each of the plurality of heat generation regions of the plurality of heater units based on the second setting heat flux for activation and the corresponding group for activation, respectively. In the substrate heater system according to claim 7,
When the difference between the measured temperature and the set temperature is less than the second temperature difference,
The preceding heat flux setting unit outputs the corresponding setting heat flux corresponding to the operation mode at the time of control,
The PID control unit outputs the control heat flux based on the measured temperature and the set temperature,
The ratio setting unit determines a control automatic mode that is one of the plurality of substrate heating modes, and outputs a control automatic correspondence group as a correspondence group corresponding to the control automatic mode,
The temperature control unit controls a heat flux in each of the plurality of heat generation regions of the plurality of heater units based on the correspondence setting heat flux, the control heat flux, and the control automatic correspondence group, respectively. . A substrate heater system according to any one of claims 1 to 8, provided in a film forming chamber,
A substrate holding unit provided in the film forming chamber, capable of holding a substrate, heated by the substrate heater, and serving as a ground electrode;
A vacuum processing apparatus comprising: a discharge electrode provided in the film forming chamber and provided to face the substrate holding portion. A temperature control method using a substrate heater system,
Here, the substrate heater system is:
A plurality of heater units arranged in parallel;
A temperature sensor for measuring the temperature of an object heated by the plurality of heater units;
A temperature control unit for controlling heat generation of the plurality of heater units,
Each of the plurality of heater units includes a plurality of heat generation regions,
The temperature control method includes:
(A) a temperature control unit acquiring the measured temperature;
(B) The temperature control unit determines that the measured temperature is the set temperature based on the plurality of coefficient values, the set temperature, and the measured temperature that are set in advance corresponding to the plurality of heat generation regions of the plurality of heater units. And a step of controlling heat fluxes in the plurality of heat generating regions of the plurality of heater units, respectively. The temperature control method according to claim 10,
Here, the substrate heater system is:
Each of the plurality of heater units is distributed in a plane and has a plurality of heat generating portions,
The step (b)
(B1) In the plurality of heating units of the plurality of heater units, the temperature control unit is configured so that the measured temperature becomes the set temperature based on the plurality of coefficient values, the measured temperature, and the set temperature. A temperature control method comprising a step of controlling each of the heat fluxes. The temperature control method according to claim 10,
Here, the substrate heater system is:
Each of the plurality of heater units includes at least one bar heater,
The bar heater has a plurality of heat generating parts,
The step (b)
(B1) In the plurality of heating units of the plurality of heater units, the temperature control unit is configured so that the measured temperature becomes the set temperature based on the plurality of coefficient values, the measured temperature, and the set temperature. A temperature control method comprising a step of controlling heat fluxes. The temperature control method according to any one of claims 10 to 12,
The step (a) includes:
(A1) the temperature control unit includes a step of acquiring an operation mode at the time of control among a plurality of operation modes of the vacuum processing apparatus in which the plurality of heater units are installed;
The step (b)
(B2) In addition to the plurality of coefficient values, the measured temperature, and the set temperature, the temperature control unit is preset in correspondence with the plurality of operation modes, and is controlled during the control of a plurality of set heat fluxes. A temperature control method for respectively controlling heat fluxes in the plurality of heat generation regions of the plurality of heater units based on corresponding setting heat fluxes corresponding to the operation modes. The temperature control method according to claim 13,
The step (a) includes:
(A2) the temperature control unit includes a step of acquiring a substrate heating mode at the time of control among the plurality of substrate heating modes;
The step (b)
(B3) The temperature control unit performs PI control or PID control based on the measured temperature and the set temperature, and outputs a control heat flux;
(B4) The temperature control unit outputs a corresponding group corresponding to the substrate heating mode at the time of control among the plurality of groups of the plurality of coefficient values set in advance corresponding to the plurality of substrate heating modes. Steps,
(B5) The temperature control method, wherein the temperature control unit controls the heat fluxes in the plurality of heat generation regions of the plurality of heater units based on the correspondence setting heat flux, the control heat flux, and the correspondence group, respectively. The temperature control method according to claim 14, wherein
(C) When the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference, the temperature control unit is set in advance for the first startup instead of the corresponding set heat flux and the control heat flux. Further comprising outputting a set heat flux,
The step (b4) includes
(B41) When the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference, the temperature control unit determines that the temperature rise mode is one of the plurality of substrate heating modes, and the activation Outputting a corresponding group for activation as the corresponding group corresponding to the temperature rising mode,
The step (b5) includes
(B51) When the difference between the measured temperature and the set temperature is equal to or greater than a first temperature difference, the temperature control unit is configured to select the plurality of start-up set heat fluxes and the start-up correspondence group based on the plurality of start-up correspondence groups. A temperature control method comprising a step of respectively controlling heat fluxes in the plurality of heat generating regions of the heater unit. The temperature control method according to claim 15,
(D) When the difference between the measured temperature and the set temperature is greater than or equal to a second temperature difference and less than the first temperature difference, the temperature control unit is set in advance instead of the first set heat flux for startup. A step of outputting a setting heat flux for second activation,
The step (b4) includes
(B42) When the difference between the measured temperature and the set temperature is equal to or greater than a second temperature difference and less than the first temperature difference, the temperature control unit further includes a step of outputting the activation corresponding group.
The step (b5) includes
(B52) When the difference between the measured temperature and the set temperature is greater than or equal to a second temperature difference and less than the first temperature difference, the temperature control unit determines that the second set heat flux for startup and the corresponding group for startup are And a step of controlling heat fluxes in the plurality of heat generation regions of the plurality of heater units, respectively, based on the temperature control method. The temperature control method according to claim 16, wherein
(E) when the difference between the measured temperature and the set temperature is less than a second temperature difference, the temperature control unit further includes a step of outputting the corresponding set heat flux corresponding to the operation mode at the time of control;
The step (b3)
(B31) When the difference between the measured temperature and the set temperature is less than a second temperature difference, the temperature control unit includes a step of outputting the control heat flux based on the measured temperature and the set temperature. ,
The step (b4) includes
(B43) When the difference between the measured temperature and the set temperature is less than a second temperature difference, the temperature control unit determines that the control automatic mode is one of the plurality of substrate heating modes, and the control automatic A step of outputting a control automatic response group as a corresponding group corresponding to the mode;
The step (b5) includes
(B53) When the difference between the measured temperature and the set temperature is less than a second temperature difference, the temperature control unit, based on the corresponding set heat flux, the control heat flux, and the control automatic correspondence group, A temperature control method for controlling heat fluxes in the plurality of heat generation regions of the plurality of heater units, respectively. (F) a step of holding the substrate in a substrate holding unit as an object to be heated in the film forming chamber;
(G) using the temperature control method according to any one of claims 10 to 17, heating the substrate holding part and the substrate;
(H) In the film forming chamber, a plasma of a source gas is generated between the substrate holding portion as a ground electrode and a discharge electrode provided to face the substrate holding portion, and a thin film is formed on the substrate. A method for producing a thin film comprising: forming a film.

Images